Disease activity measure

Components

Interpretation of results

DASa

In clinical practice DAS28 (including 28 joints: wrists, metacarpophalangeal joints, proximal interphalangeal joints, elbows, shoulders, knees) is used most commonly. Score is evaluated using a calculator that takes into account:

1) Number of swollen joints

2) Number of tender joints (including 28 joints: wrists, metacarpophalangeal joints, proximal interphalangeal joints, elbows, shoulders, knees)

3) ESR or CRP

4) Patient’s global assessment of disease activity using VAS (0-100)

Score range: 0-9.4

Interpretation:

<2.6: Remission

≤3.2: Low activity

>3.2 and ≤5.1: Moderate activity

>5.1: High activity

Evaluation of treatment response:

– Good: Change in activity ≥1.2 and low disease activity

– Moderate: Change >0.6 and <1.2 and low or moderate disease activity, or change ≥1.2 and high or moderate disease activity

– No response: Change <0.6 or <1.2 and high activity

SDAI

Takes into account same joints as DAS28 but does not require a calculator

SDAI score =

Number of tender joints

+ Number of swollen joints

+ Patient’s global assessment of disease activity using VAS (0-10 cm)

+ Physician’s global assessment of disease activity using VAS (0-10 cm)

+ Plasma CRP levels (0.1-10 mg/dL)

Score range: 0.1-86

Interpretation:

Score ≤3.3: Remission

≤11: Low activity

>11 and ≤26: Moderate activity

>26: High activity

Evaluation of treatment response:

– Significant improvement: Change >21

– Moderate improvement: Change 10-21

– No improvement: Change ≤9

CDAI

Identical to SDAI but does not take CRP into account

Score range: 0.1-76

Interpretation:

Score ≤2.8: Remission

≤10: Low activity

>10 and ≤22: Moderate activity

>22: High activity

ACR/EULAR remission criteria

All must be fulfilled:

– Tender joint count ≤1

– Swollen joint count ≤1

– Plasma CRP (mg/dL) ≤1

– Patient’s global assessment of disease activity using VAS (0-10) ≤1 or SDAI ≤3.3

Criteria recommended by EULAR for assessment of effectiveness of treatment in clinical practice

In clinical practice, the CDAI is the most commonly performed measure of disease activity. Other measures are used mainly in research settings.

a www.das-score.nl/das28/en/